The object of the invention is a method and a device for measuring the quality of connection in tobacco industry's articles.
The invention is used in the tobacco industry, in particular to measure the quality of adhesive connection between the wrapper and the filler of a rod used in the tobacco industry.
At present, both filter made of a single filter material and of multiple different materials, so-called multi-segment filters, are used. Rods containing a single kind of filter material are formed by cutting a continuous filter rod which is formed by wrapping a filter fibre strand with a wrapper. In the subsequent production process, the rods are cut into a plurality of individual filters applied to cigarettes. Multi-segment rods are formed by cutting a continuous rod which is formed by wrapping multiple segments of different filter materials. In both cases, a rotary cutting head with knives situated on its circumference is used. In case of multi-segment rods, the cutting of the rods usually consists in cutting one of the segments into halves. In the subsequent production process, multi-segment rods are cut into a plurality of individual filters applied to cigarettes. In a finished cigarette, the first segment is adapted to be held by the smoker in the mouth. It is commonly expected that during smoking this segment does not fall out of a cigarette or fall into the smoker's mouth. With regard to filters made of a single material it is also expected that it will not move relative to the wrapper. A commonly used method of segment fixing is to glue them to the wrapper. At present, the cigarette manufacturers use various filter materials as well as various filter wrapper materials. From the viewpoint of adhesive bonding of filter materials and wrapper materials, a very significant issue is the spread of the adhesive in the space between the surfaces to be glued, and the penetration of the adhesive into the structures of both the wrapper and the filter material. These are the factors determining the force holding the segments in the wrapper, i.e. the force of connection of the segments with the wrapper. One or more glue paths are used to fix the segments, whereas such paths may have different shapes. Among the manufacturers of tobacco industry products there is a demand for a device checking the quality of connection of the segments with the wrapper in particular of short segments placed at the end of the filter tip for which the surface to be glued with the wrapper is small. Moreover, there is a demand for a device checking the tobacco filler's holding force in cigarettes depending on the elasticity of tobacco, the filling degree and the friction forces between the tobacco fibres and the wrapper material.
The U.S. Pat. No. 5,144,845 document disclosed a device designed to check the adhesive connection, comprising a movable carriage on which one of the tested materials may be fixed and an anvil in which the second of tested materials may be mounted. The device also comprises means for the application of glue in order to form a glue layer between tested materials. These means are mounted on a movable carriage. Moreover, the device comprises carriage moving means, and means designed to push the carriage and the anvil which, together, connect both materials with each other with the layer of applied glue placed between them. Then, an attempt to separate the tested materials by pushing the carriage and the anvil apart is made and the force needed to separate them is measured by means of a strain gauge.